Changes in expression of K
channels in neonatal rat cardiac myocytes after exposure to high concentrations of glucose. Cultured neonatal rat cardiac myocytes exposed to glucose at final concentrations of 10 mM, 20 mM and 30 mM were used to compare with the control, which was incubated with 5.5 mM glucose. Cells were also exposed to 24.5 mM mannitol to produce the same osmolarity (317 mOsmol/L) as that produced when using the highest concentration of glucose (30 mM). After 24 hours of incubation, cells were prepared for Western blot analysis. Quantification of protein levels using SUR-2A or Kir6.2 over β-actin indicated as means with SE (n = 4 per group) in each column are presented in the lower panel. *P < 0.05, **P < 0.001 compared to control.